The problem with this reasoning is that some heretical ideas are perhaps correct, some are just nuts, and some are both nuts and very damaging. While it is true

The problem with this reasoning is that some heretical ideas are perhaps correct, some are just nuts, and some are both nuts and very damaging. While it is true that moral fashions and taboos of discourse can exclude good ideas, the inverse does not follow. It does not follow that an excluded idea is therefore good. I think this even works in previous ages. While medieval heretics did not deserve the punishments they received, the majority of them were probably nuts and believed things that were at least as irrational as the dominant paradigms of the time. They called Einstein crazy. They also called Otis Eugene Ray crazy. https://en.wikipedia.org/wiki/Time_Cube https://en.wikipedia.org/wiki/Time_Cube Would you have considered letting Otis Eugene Ray go from an engineering position if he started arguing for his bizarre stuff? They also called Willis Carto crazy: https://en.wikipedia.org/wiki/Willis_Carto https://en.wikipedia.org/wiki/Willis_Carto How about those heresies? Would you want him on your staff if he were outspoken about how the Holocaust didn't happen and Jews are responsible for all the evils of the world? Seems to me that a great many of those being excluded from present discourse are being excluded for arguing for very strong forms of biological determinism coupled with a naturalistic fallacy (if it's natural, it's therefore good) argument for the legitimacy of racism and sexism. Those are dubious ideas with a demonstrated recent track record of motivating acts that cause tremendous harm to a lot of people. They're not heresies of the beneficial sort.